TEXAS TECH UNIVERSITY
CENTER FOR MULTIDISCIPLINARY RESEARCH IN TRANSPORTATION
Project Summary Report 0-2108-S
PROJECT SUMMARY REPORT
Project 0-2108
Authors: Richard Zartman, John Borrelli,
Cynthia McKenney and Ron Sosebee
December 2003
Integrated Roadside Management Manual
TxDOT, as well as other public
and private agencies, needs to
occasionally update its printed
materials to make them current.
The need to update the Roadside
Vegetation Management
Manual, a publication of the
Texas
Department
of
Transportation (TxDOT), can be
attributed to a better understanding
of the roadside environment. This
document is a total revision of
TxDOT Manual Notice 96-1
(March 1, 1996), which itself was
an update of the November 1993
edition. The 1996 document was
a modified version of the 1993
publication with various pages and
Figure 1. Woody plants encroaching on line of sight
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chapters removed, recycled and
replaced with changes.
This Roadside Vegetation
Management Manual is divided
into two components. These are
functional components and
aesthetic components. As in all
TxDOT decisions, safety is the
primary concern. When no safety
concerns are present, the functional
components of the roadside
management system are high priority.
When the functional components of the
roadside management system are
satisfied, the aesthetic components are
considered. The users of Texas
highways want safe, functional and
pleasing highway rights-of-way. This
document aids TxDOT professionals
and others in maintaining roadside
vegetation.
of numerous journals and other
departments of transportation, they
relied greatly on the work and
experience of TxDOT personnel and
TxDOT published guidelines. These
reviews and the previous Roadside
Vegetation Management Manual were
the basis for this complete rewrite of the
previous manual.
What We Found…
The results of our literature review
indicate that TxDOT has kept current
on the management of the highway
What We Did…
rights-of-way. There are several factors
that influence the management of
Four topic-specific literature reviews highways in Texas.
were written early in this study. The
literature reviews were on the following The first and foremost is the concern
topics: seeding and sodding, erosion/ for safety to the traveling public.
sedimentation, mowing, and herbicides. TxDOT has safety as the number one
While these literature reviews were priority. If there are view obstructions
original efforts drawing on the resources or other potential problems, TxDOT
Figure 2. Honey Mesquite has the potential to cause a flat tire
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responds and corrects these problems
as rapidly as possible.
Some people wish the highway rightsof-way to be intensively maintained.
Other people wish to pay minimal taxes
to maintain the highway rights-of-way.
TxDOT must find a balance between
these two views. As part of our work,
we have heightened TxDOT’s
awareness of these concerns. TxDOT
strongly recommends the coordination
of the herbicide applications and
mowing operations. Mowing
immediately after a herbicide
application would make the herbicide
application useless.
TxDOT
recommends a mowing height that will
be low enough, to prevent view
obstructions, but high enough to
maintain the vegetation cover and
minimize erosion.
Additionally, TxDOT is keenly aware of
the public’s reception to wildflowers.
TxDOT recommends the delaying of
mowing to foster the growth and
development of wildflowers along the
highway rights-of-way. They also realize
that weeds such as sunflowers and
Johnson grass require different
management techniques. Sunflowers
must be mowed before they go to seed
to lessen future problems. Johnson
grass, however, cannot be controlled by Manual Notice 96-1), we recommend
mowing, and must be controlled by continued coordination between the
personnel charged with maintaining the
herbicide application.
highway rights-of-way.
The Researchers
Recommend...
After reviewing the previous TxDOT
manual “Roadside Vegetation
Management Manual” (TxDOT
Figure 3. Wildflowers increase tourism
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For More Details…
The research is documented in the following report:
Report No. 0-2108 - Integrated Roadside Management Manual
Research Supervisor: Richard Zartman, Ph.D., Texas Tech University
Project Director: Steve Prather, Vegetation Management Section
To obtain copies of the reports, contact the Center for Transportation Research Library at (512) 232-3126.
TXDOT IMPLEMENTATION STATUS
December 2003…
This research was pursued as a total revision of the TxDOT Roadside Vegetation Management Manual.
The resulting manual is divided into two components: functional and aesthetic. The functional component
addresses safety issues and when the safety issues are satisfied the aesthetic components are considered.
The users of Texas highways want safe, functional, and visually pleasing highway rights-of-way. This
document will be used statewide to maintain roadside vegetation for Texas highway users.
For more information, contact; William E. Knowles, P.E., RTI Research Engineer, at (512) 465-7403
or e-mail wknowle@dot.state.tx.us.
Your Involvement Is Welcome...
Disclaimer
This research was performed in cooperation with the Texas Department of Transportation and the U.S.
Department of Transportation, Federal Highway Administration. The content of this report reflects the
views of the authors, who are responsible for the facts and accuracy of the data presented herein. The
contents do not necessarily reflect the official view or policies of the FHWA or TxDOT. This report does
not constitute a standard, specification, or regulation, nor is it intended for construction, bidding, or permit
purposes. Trade names were used solely for information and not for product endorsement.
The University of Texas at Austin
Center for Transportation Research Library
3208 Red River #115
Austin, TX 78705-2650
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